A couple of things
1) Unless you are coding a repeat group, don't set Rp<get|set>Type to Complex. Use Function instead. Complex adds the indecies that you will not need except in a repeat group
2) In the case of the generated function you return the string that is your MAC address. For example return "00:40:9D:BA:DB:AD";
3) "Also if i search for the fucntion in the folder it is not beign used still a new mac address is given by it."
I am not sure what yo are asking. The only time function getMacAddress is called is when a "get" request comes in from the browser, either on its own, or after a set.
4) theTaskDataPtr is a data structure maintained by the advanced web server engine. You do NOT have access to it except as a void *. Think of it as a handle. There are some AWS functions (for getting cookies, getting access to buffers in the AWS....) to which you pass that theTaskDataPtr. Do not attempt to change it. It is only for the AWS's use. Se the document Advanced web server toolkit. In that document are writeups on all of the AWS access routines that might use that structure
5) Last, if you update through the package mgr (ESP) in the documentation directory, there are a set of white papers. On eis called (I think) Using the advance web serevr. It is an explaination of how to build an AWS application from the group up. It also includes an AWS application. You might want to look at it.